Single-center retrospective study 49 pts w/ primary angiitis CNS (PACNS) stratified by vessel size. Vessel size dx by imaging & neuroradiologists. Small vessel involv(n  9) was significantly assoc w/ +Biopsies, CTX use, functional decline & more relapses. https://t.co/DF6DknoPxY https://t.co/puc6nvEAut